Safety Of Janus Kinase Inhibitors Research Articles

Safety of Janus kinase inhibitors compared to biological DMARDs in patients with rheumatoid arthritis and renal impairment: the ANSWER cohort study

Data on the safety of Janus kinase inhibitors (JAKis) in patients with renal impairment are lacking. This study aimed to investigate the safety of JAKis compared to biological (b) DMARDs in patients with rheumatoid arthritis (RA) and renal impairment. We used a multi-centre observational registry of patients with RA in Japan (the ANSWER cohort). We assessed the drug retention rates of b/targeted synthetic DMARDs with different modes of action (tumour necrosis factor inhibitors (TNFis), immunoglobulins fused with cytotoxic T-lymphocyte antigen (CTLA-4-Ig), interleukin-6 receptor inhibitors (IL-6Ris), and JAKis) in patients with RA stratified by pre-treatment estimated glomerular filtration rate (eGFR) levels. The time to discontinuation of bDMARDs or JAKis was analysed using a multivariate Cox proportional hazards model This study included 3775 patients, who were classified into three groups (the normal group (eGFR ≥ 60 mL/min/1.73 m2): 2893 patients; CKDa group (eGFR 45–60 mL/min/1.73 m2): 551; and CKDb group (eGFR < 45 mL/min/1.73 m2): 331). In the CKDb group, the 12-month drug retention rate due to adverse events (AE) was the lowest in patients treated with JAKi (TNFi: 93.1%; IL-6Ri: 94.1%; CTLA-4-Ig: 92.3%; JAKi: 75.1%). In the normal and CKDa groups, drug retention rates due to AE were similar among patients treated with bDMARDs and JAKi. In contrast, drug retention rates due to inefficacy were similar between bDMARDs and JAKis in all groups. In the Cox-proportional model, in the CKDb group, TNFi, IL-6Ri, and CTLA-4-Ig showed lower incidence of drug discontinuation due to AE than JAKis (TNFi: hazard ratio = 0.23 (95% confidence interval 0.09–0.61), IL-6Ri: 0.34 (0.14–0.81), CTLA-4-Ig: 0.36 (0.15–0.89)). JAKis showed the lowest drug retention due to AE in patients with moderate-to-severe and severe renal impairment (eGFR < 45 mL/min/1.73 m2). Physicians should pay more attention to renal function when using JAKis than when using bDMARDs.

Janus kinase inhibitors and tumour necrosis factor inhibitors show a favourable safety profile and similar persistence in rheumatoid arthritis, psoriatic arthritis and spondyloarthritis: real-world data from the BIOBADASER registry

ObjectivesTo compare the safety of Janus kinase inhibitors (JAKi) with that of tumour necrosis factor inhibitors (TNFi) and determine drug persistence among patients with rheumatoid arthritis (RA) and spondyloarthritis (SpA).MethodsWe...

Tofacitinib in Pregnancy: Assessing Pregnancy and Infant Outcomes, Cord Blood, and Breast Milk Concentrations

Janus kinase (JAK) inhibitors are effective anti-inflammatory agents for treatment of ulcerative colitis (UC).1 According to drug regulatory agencies and international guidelines, JAK inhibitors should be avoided during pregnancy and lactation.2-4 The existing evidence on safety of JAK inhibitors during pregnancy is scarce and almost exclusively limited to tofacitinib.4-7.

P718 Observational real-world evidence on the efficacy and safety of Janus Kinase inhibitors (JAKi) in the treatment of moderate to severe Active Ulcerative Colitis (UC)

Abstract Background Janus kinase inhibitors (JAKi) are the first orally administered treatment for Ulcerative Colitis (UC). The JAK family comprises of four intracellular tyrosine kinases inhibitors (JAK1, JAK2, JAK3 and Tyrosine Kinase 2). Inhibition of the JAK kinases lead to dampening of the inflammatory cytokines which drive Inflammatory Bowel Disease (IBD). Tofacitinib was the first generation pan-JAKi. This was followed by second generation JAKi: Filgotinib and Upadacinib which preferentially inhibit JAK1. We report on the real-world evidence on the efficacy and safety of JAKi in the treatment of UC in a tertiary IBD treatment centre. Methods Patients attending the IBD clinic at weeks 8-12 of initiation of therapy were included. Baseline demographics, disease activity and previous therapies were recorded. Clinical response was measured using the SCCAI and biochemical response was measured using calprotectin and CRP. We defined clinical response as ≥3 points reduction from baseline SCCAI, and clinical remission as SCCAI Score of &amp;lt;2.5, and / or biochemical remission as a CRP of less than 5 mg/L and a calprotectin level of &amp;lt; 250 mg/g. We also assessed treatment persistence, and the reasons for treatment cessation. Results The UC populations are shown in Table 1. 52 patients were included and an additional 24 patients who discontinued therapy early on were assessed to review secondary outcomes. Table 1 summarises the comparative outcomes of the JAKi. 81% and 63% of patients achieved clinical and biochemical remission respectively. Overall, 31% discontinued treatment due to lack of efficacy or adverse events. 60% of patients reported adverse events (AEs), 25 % of patients discontinued treatment due to AEs and 84% of patients continued treatment despite reporting AEs. The most common AEs were hypercholesteremia and cold and flu like symptoms and the most common AEs related with treatment discontinuation were recurrent infection or persistent deranged liver functions contributed to patients’ history of primary sclerosing cholangitis. No Serious Adverse Events were reported. 60% of patients on tofacitinib developed side effects and persisted with therapy, which included hypercholesteremia (67%), shingles (11%), flu like symptom (11%) and hair loss (11%). 53% had side effects with Filgotinib; hypercholesteremia (25%), cold like symptoms (25%), chest infection (13%), shingles (13%), acne (13%). 68% developed side effects with Upadacitinib; reports of acne (20%), cold and flu (33%), shingles and mood swings (7%) and high cholesterol (67%). Conclusion In this real-world cohort of UC patients, JAKi was effective in inducing remission and had an acceptable safety profile. The observed safety profile was as expected compared to clinical data results.

Efficacy and safety of JAK inhibitors in rheumatoid arthritis: update for the practising clinician.

Janus kinase (JAK) inhibitors, including tofacitinib, baricitinib, upadacitinib and filgotinib, are increasingly used in the treatment of rheumatoid arthritis (RA). There has been debate about their safety, particularly following the issuance of guidance by regulatory agencies advising caution in their use in certain patients. The registrational clinical trials and registry data of JAK inhibitors did not identify a difference in therisk of major adverse cardiovascular events (MACEs), venous thromboembolism, malignancies or infections (other than herpes zoster) with a JAK inhibitor versus abiologicDMARD. In the ORAL Surveillance trial, which enrolled patients >50 yearsof age with ≥1 cardiovascular risk factor, tofacitinib was statistically inferior to TNF inhibitors for the occurrence of MACEs and malignancy. Further post hoc analysis of the data revealed that anageof ≥65 years, ahigh baseline cardiovascular risk, ahistory of smoking, sustained inflammation, disease activity and suboptimal treatment of cardiovascular comorbidities all increase the risk of these outcomes. The guidance issued by regulatory agencies should be carefully considered to ensure appropriate and safe treatment of patients with RA without undertreatment of patients who might benefit from JAK inhibitor, as well as biologic, treatment. As always, the risks associated with the use of these agents, treatment goals, costs and patient preferences should be discussed with the patient.

Janus Kinase Inhibitors and Interstitial Lung Disease Associated With Pediatric Rheumatic Diseases: An Unexplored Field.

Rheumatic diseases are often complicated by lung disease, commonly presenting as interstitial lung disease (ILD), with potentially detrimental consequences for patient survival. Although less frequent in pediatric patients, pulmonary involvement may be observed in almost all childhood-onset rheumatic conditions. The development of biological disease-modifying anti-rheumatic drugs has significantly improved clinical outcomes. However, disease remission is not always complete or long-lasting, and treatment may need to be discontinued due to adverse effects. A novel class of drugs, namely Janus kinase inhibitors (JAKis), has been proposed to provide a significant survival benefit for patients with rheumatic diseases. Despite the ample literature on the efficacy and safety of JAKis in rheumatic disease, only a few studies have investigated the effectiveness of these drugs in patients with pulmonary involvement, and only two case reports have presented results in pediatric patients. We provide an overview of the rationale for using JAKis in ILDs associated with rheumatic disease and summarize the main studies evaluating their efficacy in both adult and pediatric patients. The present review highlights the need for controlled long-term studies to assess the efficacy and safety of JAKis in pediatric rheumatic disease complicated by lung disease.

Jak inhibitors in vitiligo: a meta analysis.

Jak inhibitors in vitiligo: a meta analysis.

JAK Inhibitors in Solid Organ Transplantation.

Janus kinase (JAK) inhibitors are a novel group of immunosuppressive drugs approved to treat certain rheumatic and allergic disorders; however, their efficacy in the regulation of alloimmune responses after solid organ transplantation has not yet been elucidated. In the present review, we have summarized the results of invitro, invivo, experimental, and clinical trial studies about the efficacy and safety of JAK inhibitors in improving allograft survival in solid organ transplantations, including kidney, heart, lung, and liver transplants. Moreover, reports on administering JAK inhibitors to steroid-resistant patients with graft versus host disease (GvHD) after solid organ transplantation have been reviewed. Overall findings are suggestive of a beneficial role for JAK inhibitors in organ transplantation: for example, they have been shown to improve allograft function, reduce the rate and score of acute rejection, downregulate the expression of proinflammatory cytokines and adhesion molecules, and decrease oxidative stress. However, the adverse effects of these drugs, in particular bone marrow suppression and infection, remain an obstacle.

Safety of Janus Kinase Inhibitors: A Real-World Multicenter Retrospective Cohort Study.

Oral Janus kinase inhibitors (JAKis) represent an effective strategy for rheumatoid arthritis (RA) treatment. A previous study supported that tofacitinib (TOF) is associated with higher incidence of cardiovascular (CV) and neoplastic events compared to tumor necrosis factor inhibitors. Given the apparent discrepancy between these data and real-world experience, we aimed to investigate the safety and efficacy of the available JAKis in a multicenter cohort. We retrospectively evaluated patients with RA who ever received 1 JAKi (TOF, baricitinib [BAR], upadactinib [UPA], filgotinib [FIL]) from 4 tertiary care centers in Milan, Italy. Outcomes related to JAKi safety were recorded, particularly major CV events as well as adverse events of special interest (AESIs), which included serious infections, opportunistic infections, venous thromboembolism, herpes zoster infections, liver injury, malignancies, and deaths; retention rates were also calculated. Further analyses included patients fulfilling the risk factors suggested to influence TOF safety. Six hundred eighty-five patients were included and received BAR (48%), TOF (31%), UPA (14%), or FIL (7%) as first-line innovative treatment prior to a biologic. Of a total of 1137 patient-years of observation, we recorded 1 stroke and 123 (18%) AESIs, including 3 deaths, all a result of severe infections. Among patients with a higher CV risk, we observed a higher frequency of AESIs (23%). Our real-world data confirm that JAKis are effective and carry a low risk of AESIs, especially in patients who do not display CV risk factors at baseline. Our study could not identify differences between JAKis. Different safety profiles should be defined in larger prospective cohorts.

Drug Retention Rates and the Safety of Janus Kinase Inhibitors in Elderly Patients with Rheumatoid Arthritis.

We examined the real-world drug retention rate and safety data of Janus kinase inhibitors (JAKis) in elderly patients with rheumatoid arthritis (RA). This study enrolled 133 RA patients (≥65 years) with sufficient clinical data who were initiated with JAKis during the study period. These patients were divided into two groups: the very elderly group (≥ 75 years) and the elderly group (65 ≤ years < 75). The drug retention rates of JAKis were compared using Kaplan-Meier curves. The discontinuation rates of JAKis were as follows: lack of effectiveness 27 (20.3%), adverse events (AEs) 29 (21.8%), and remission 2 (1.5%). There was no significant difference in the overall drug retention rate between the very elderly group (≥75 years) and the elderly group. Furthermore, the overall drug retention rates of JAKis were not affected by gender, methotrexate use, and anti-citrullinated protein/peptide antibody (ACPA) status. The discontinuation rates of JAKis due to AEs were comparable both in the very elderly group (≥75 years) and the elderly group (65 ≤ years < 75). Whereas chronic lung disease and hypoalbuminemia were independently associated with discontinuation rates due to AEs, the overall drug retention rates were significantly lower in patients treated with the approved dose of JAKis than in those treated with a reduced or tapered dose. Our results suggest that the overall drug retention rate of JAKis in very elderly patients (≥75 years) was comparable with that in elderly patients (65 ≤ years < 75). The discontinuation rates of JAKis due to AEs were also comparable both in very elderly group patients and elderly patients.

Recommendations for risk minimization when using Janus kinase inhibitors for the treatment of chronic inflammatory skin diseases.

In accordance with article 20 of Regulation (EC) No 726/2004, the Pharmacovigilance Risk Assessment Committee (PRAC) of the European Medicines Agency (EMA) has re-evaluated the safety of Janus kinase inhibitors for the treatment of inflammatory diseases and formulated safety information deviating from the previous indications in the respective summary of product characteristics of the products concerned. These refer to the consideration of a possibly increased risk of venous thromboembolic or severe cardiovascular events, an increased infection rate and an increase in the prevalence of skin cancer across drugs and indications. Therefore, in patients with independent risk factors (age 65 years and older, smokers or former smokers, patients with oral contraception or hormone replacement therapy and other risk factors), it is recommended to use Janus kinase inhibitors therapeutically only if there are no suitable treatment alternatives. To facilitate a pragmatic and thorough detection of high-risk patients in everyday clinical practice, an interdisciplinary checklist was developed that is suitable as a working tool from the perspective of the dermatologist.

Efficacy and safety of Janus kinase inhibitors in axial spondyloarthritis.

Skin manifestations are common in axial spondyloarthritis (axSpA) and may precede axial involvement. Multidisciplinary management of patients with spondyloarthritis (SpA) is essential. Combined dermatology-rheumatology clinics are established for early recognition of the disease, comorbidities and a comprehensive treatment approach. Treatment options for axSpA are limited because conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) and glucocorticoids are ineffective for axial symptoms. Janus kinase inhibitors (JAKi) are targeted synthetic disease-modifying antirheumatic drugs (tsDMARDs) that decrease transduction signalling to the nucleus, resulting in a reduced inflammatory response. Currently, tofacitinib and upadacitinib are approved for treating axSpA in patients with inadequate response to TNF inhibitors (TNFi). Upadacitinib has shown efficacy in non-radiographic axSpA (nr-axSpA), suggesting that JAKi are efficacious across the spectrum of axSpA. The availability of JAKi has opened more options for patients with active axSpA based on the efficacy data and the ease of administration.

Comparative effectiveness of JAK inhibitors and biologic disease-modifying antirheumatic drugs in patients with rheumatoid arthritis.

We aimed to compare the effectiveness and safety of Janus kinase inhibitors (JAKi) vs. biologic disease- modifying antirheumatic drugs (bDMARD) in Korean patients with rheumatoid arthritis (RA) who had an inadequate response to conventional synthetic DMARDs. A quasi-experimental, multi-center, prospective, non-randomized study was conducted to compare response rates between JAKi and bDMARDs in patients with RA naïve to targeted therapy. An interim analysis was performed to estimate the proportion of patients achieving low disease activity (LDA) based on disease activity score (DAS)-28- erythroid sedimentation rate (ESR) (DAS28-ESR) at 24 weeks after treatment initiation and to evaluate the development of adverse events (AEs). Among 506 patients enrolled from 17 institutions between April 2020 and August 2022, 346 (196 JAKi group and 150 bDMARD group) were included in the analysis. After 24 weeks of treatment, 49.0% of JAKi users and 48.7% of bDMARD users achieved LDA (p = 0.954). DAS28-ESR remission rates were also comparable between JAKi and bDMARD users (30.1% and 31.3%, respectively; p = 0.806). The frequency of AEs reported in the JAKi group was numerically higher than that in the bDMARDs group, but the frequencies of serious and severe AEs were comparable between the groups. Our interim findings reveal JAKi have comparable effectiveness and safety to bDMARDs at 24 weeks after treatment initiation.

Efficacy and safety of Janus kinase inhibitors in patients with psoriasis and psoriatic arthritis: a systematic review and meta-analysis.

To evaluate the efficacy and safety of Janus kinase (JAK) inhibitors (Jakinibs) in the treatment of psoriasis and psoriatic arthritis (PsA). Databases including PubMed, Embase, Web of Science, and Cochrane Library were searched for randomized controlled trials on the efficacy and safety of Jakinibs in treating psoriasis and PsA from inception to July 2021. A systematic review and meta-analysis were performed to estimate pooled relative risk (RR) and 95% confidence interval (CI). Seventeen clinical trials (16 publications) comprising 6802 patients were included. All Jakinibs demonstrated significantly higher response rates compared with placebo (ACR20: RR 2.09, 95% CI 1.90-2.30; PASI75: RR 4.03, 95% CI 3.13-5.18). Within the subgroup analysis, the response rates defined by ACR20 were highest for filgotinib (RR 2.40, 95% CI 1.67-3.45), followed by upadacitinib, tofacitinib, and deucravacitinib. The proportion of patients achieving PASI75 response in the tofacitinib 10mg twice daily group was significantly higher than that in the tofacitinib 5mg group. Regarding safety, the incidence of adverse events (AEs) was significantly higher for Jakinibs compared with placebo (RR 1.17, 95% CI 1.11-1.23). Of note, a considerable increase in the risk of infections including upper respiratory tract and herpes zoster infection was observed among patients in the treatment group. For tofacitinib, upadacitinib, and filgotiniband, infection was the most prevalent AE. Moreover, AEs in the 10mg tofacitinib group were higher than those in the 5mg tofacitinib group. Jakinibs are efficacious interventions for the treatment of psoriasis and PsA, but they are associated with an increased risk of AEs when compared with placebo. The long-term efficacy and safety data require further evaluation. Key Points • This systematic review investigated and compared the efficacy and safety of different Jakinibs including the novel selective TYK2 inhibitors. • Jakinibs are efficacious interventions for the treatment of psoriasis and PsA. • A relatively higher dosing schedule of Jakinibs is associated with increased toxicity.

Efficacy and safety of IL inhibitors, TNF-α inhibitors, and JAK inhibitors in patients with ankylosing spondylitis: a systematic review and Bayesian network meta-analysis.

Biologics and Janus kinase (JAK) inhibitors are commonly used to improve ankylosing spondylitis (AS) symptoms if conventional treatments are ineffective or unsuitable. This systematic review aimed to compare the therapeutic effects and safety of JAK inhibitors, tumor necrosis factor-alpha (TNF-α) inhibitors, and interleukin (IL) inhibitors in patients with AS. We retrieved literature from various databases including Web of Science, Cochrane, Embase, PubMed, China National Knowledge Infrastructure, Weipu Journal Database, SinoMed, and WanFang Data up to February 1, 2023, and evaluated the quality of the included RCTs using the Cochrane risk-of-bias tool. R 4.1.3, STATA 15.1 were employed for network meta-analyses. We identified 48 eligible articles including 8,937 patients. Ten articles were rated as "low risk", 5 as "high risk", and the others as "some concerns". In terms of efficacy, IL-17, IL-6, and JAK inhibitors were compared with TNF-α inhibitors in ASAS20 (RR =0.81, 95% CI: 0.66-0.98; RR =0.57, 95% CI: 0.35-0.95; RR =0.77, 95% CI: 0.60-0.99). IL-6 inhibitors were compared with TNF-α inhibitors in ASAS5/6 (RR =0.39, 95% CI: 0.16-0.98). IL-23, JAK inhibitors were compared with TNF-α inhibitors in BASDAI50 (RR =0.35, 95% CI: 0.20-0.60; RR =0.70, 95% CI: 0.49-0.98). IL-17 inhibitors were compared with IL-23 and IL-6 inhibitors in BASFI (MD =-1.05, 95% CI: -1.65--0.51; MD =-1.46, 95% CI: -2.02--0.97). In terms of safety, IL-6 inhibitors were compared with JAK, TNF-α inhibitors in AEs (RR =1.38, 95% CI: 1.06-1.88; RR =1.30, 95% CI: 1.01-1.70). TNF-α inhibitors are significantly superior to both IL and JAK inhibitors, and may be the preferable option to deal with the rapid progression of AS and severe functional limitations. IL-17 inhibitors may better improve the BASDAI50 response compared with JAK, IL-23, and TNF-α inhibitors. The efficacy and safety of IL-6 inhibitors are inferior to other types of drugs, indicating the low efficacy and high risk of IL-6 inhibitors.

Comparative Efficacy and Safety of Janus Kinase Inhibitors Used in Alopecia Areata: A Systematic Review and Meta-analysis.

The aim of this study was to compare the efficacy and safety of treatment with Janus kinase inhibitors for alopecia areata, measured by change in Severity of Alopecia Tool (SALT) score. A systematic review following Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines was performed using Medline, EMBASE and Cochrane library. All studies investigating the efficacy of treatments for alopecia areata were included. Primary outcomes were the proportion of patients with alopecia areata achieving 30%, 50%, 75%, 90% and 100% improvement in SALT score after treatment with a Janus kinase inhibitor. A meta-analysis was performed including all randomized controlled trials investigating Janus kinase inhibitors. A total of 37 studies matched the inclusion criteria and were included. Meta-analysis was performed based on 5 randomized studies. Regarding patients with alopecia areata defined as ≥ 50% scalp hair loss, baricitinib 4 mg once daily demonstrated the highest efficacy. However, among patients with alopecia areata defined as a SALT score ≥ 50, oral deuruxolitinib 12 mg twice daily demonstrated the highest efficacy. Deuruxolitinib and baricitinib appear to be promising drugs for the treatment of alopecia areata. However, the response depends on the dosage of the drug. More randomized trials, with identical inclusion criteria and dose and duration of treatment, are required to confirm these findings.

Alopecia Universalis in an Adolescent Successfully Treated with Upadacitinib-A Case Report and Review of the Literature on the Use of JAK Inhibitors in Pediatric Alopecia Areata.

Alopecia areata (AA) is a cell-mediated autoimmune disease in which a cytotoxic T-cell response against hair follicles occurs. AA has been demonstrated to frequently co-exist with atopic dermatitis (AD), and the coincidence of atopy predisposes to a more severe course of the disease. To date, therapeutic options in AA, especially in the pediatric population, are mainly limited to corticosteroids, irritants, sensitizers, and immunosuppressive agents. Recently, innovative therapies have emerged, among which Janus kinase (JAK) inhibitors, effective in both AD and AA, appear to be the most promising. Here, a 14-year-old girl with alopecia universalis (AU) and mild AD is demonstrated, who was successfully treated with a selective JAK1 inhibitor, upadacitinib, which has been approved for the treatment of AD in adults and children aged 12years and older. Resolution of eczema and complete hair regrowth was achieved after 3months of therapy. Apart from transient mild leukopenia at weeks 4 and 8, no adverse events were noted. Data in the literature on the efficacy and safety of JAK inhibitors in the treatment of AA in the pediatric population is based on single case reports and case series. So far, topical tofacitinib and ruxolitinib, as well as systemic tofacitinib, ruxolitinib, and baricitinib have been used off-label in this indication in children. Upadacitinib is another effective treatment option with a good benefit-risk ratio for patients with AA, including cases coexisting with AD.

Comparative efficacy and safety of JAK inhibitors and leflunomide in rheumatoid arthritis: A protocol for systematic review and meta-analysis.

Rheumatoid arthritis is the most prevalent systemic autoimmune disease among the rheumatic inflammatory musculoskeletal diseases. Currently, there is no reliable evidence regarding the comparisons of anti-rheumatic effects between leflunomide and Janus kinase inhibitors. We performed a protocol for systematic review and meta-analysis to compare the efficacy and safety of Janus kinase inhibitors and leflunomide in rheumatoid arthritis. This review has been reported following the preferred reporting items for systematic reviews and meta-analyses protocol. We will search 7 electronic databases to identify relevant studies from inception to November, 2022, which includes PubMed, MEDLINE, Embase, Cochrane Clinical Trials Database, Web of Science, China National Knowledge Infrastructure, and Chinese Biomedical Literature Database. Risk of bias will be assessed according to the Cochrane Risk of Bias Tool. The Grading of Recommendations Assessment, Development and Evaluation system will be used to judge the overall quality of evidence supporting outcomes in this work. Data analysis was performed using Reviewer Manager 5.4. The results of this systematic review will be published in a peer-reviewed journal. This systematic review will provide evidence to judge whether Janus kinase inhibitors is superior to leflunomide in patients with in rheumatoid arthritis.

Pharmacology of inhibitors of Janus kinases - Part 2: Pharmacodynamics.

As small molecules, the Janus kinase inhibitors have different, dose-dependent pharmacological binding selectivities, which, however, do not allow reliable statements about the clinical specificity of desired or side effects. It is therefore of particular importance to recognize that the pharmacodynamics of the individual Janus kinase inhibitors as a function of the treated indication is essentially determined by variable levels of regulation of the JAK/STAT signaling pathway and the pharmacokinetic conditions. Against this background, it becomes clear that only clinical trial data in defined indications are suitable for evaluating the efficacy and safety of Janus kinase inhibitors. An uncritical extrapolation of observations regarding efficacy and safety from studies of other indications should therefore only be made with due caution.

Various Application of Tofacitinib and Ruxolitinib (Janus Kinase Inhibitors) in Dermatology and Rheumatology: A Review of Current Evidence and Future Perspective.

Janus kinase inhibitors (JAKi) are anti-inflammatory medications suppressing Janus kinase-signal transducer and activator of transcription (JAK-STAT) pathway by inhibiting various cytokines receptors on the membrane of cells. Mutations and polymorphisms on JAK and STAT proteins can cause dysregulation in the balance of immune system, and ultimately result in autoimmune disorders. To record and summarize the overall efficacy and safety of JAKi in various autoimmune conditions such as alopecia areata (AA), psoriasis vulgaris (PV), psoriatic arthritis (PsA), atopic dermatitis (AD), vitiligo, hidradenitis suppurative (HS), lichen planus (LP), and pyoderma gangrenosum (PG). A thorough review of articles was performed across PubMed and Google Scholar on meta-analyses, systematic reviews, clinical trials and case studies evaluating the treatment of autoimmune disorders such as AA, PV, PsA, AD, vitiligo, LP, HS, and PG with JAKi. Duplicated data and animal experiments or in vitro/ex vivo studies were excluded. All the reviewed articles reported beneficial effects of tofacitinib and ruxolitinib application in the treatment of disorders mentioned above with the autoimmune predisposition. Tofacitinib and ruxolitinib showed potential efficacy in treating several autoimmune disorders. Based on records in the reviewed studies, both medications had acceptable safety profiles; however, physicians are recommended to outweigh the risks and benefits of such treatments for each specific condition.